Its happening to me too i'm almost convinced its a loose serpentine belt
The squeal when you turn on the AC or heater is a loose fan belt. It may be cracked and need replaced, or it may just need tightened.
Heater fan and cooling fan.
You've got trouble with your heater fan - or the motor that turns it. Same fan for both heat and AC.
That's usually an indication that the fan motor bearing is worn and/or dry.
Why does your ac and heater fan turn off and on
A squealing heater is more than likely a fan belt. It may be loose, or it may be worn and need replaced.
DON'T turn it on.
Check fan belt tension.
the heater blows warm air when fan is on low but blows cold air when fan is turn to higher setting
Sounds to me like the turn signals and the heater fan may be on the same fuse?? Jack
Ck the heater fan motor resistor .
Yes.